dalat
...
When Gerold Dobler gave a presentation about the construction of the SF at the introduction of the binoculars at the Dutch Birding Association, he told us that some aspects of the SF construction were protected by patents
Seriously though, it must be this one, which is about the "smart focus": https://www.google.ch/patents/DE102...de&dq=zeiss+binocular&ei=XppzVKCPD8y8Pf3ngLAN